PHILADELPHIA (CBS) — Looking for someplace to take the kids this fall? A unique playspace has sprung up inside Sister Cities Park, across the street from the Cathedral Basilica of Ss. Peter and Paul at 18th and the Benjamin Franklin Parkway.

The new “Imagination Playground” has giant, soft building blocks in various shapes that children can use to build whatever comes to mind.

“We are so excited,” says Paul Levy, president and CEO of the Center City District. “This park, Sister Cities, has been so successful for families with kids. But we knew last October, when we turned off the water, it got incredibly quiet.

“So my staff consulted nearby schools and institutions and came up with this wonderful idea — this foam rubber ‘Imagination Playground.’ So we drained the pond, put in a foam rubber surface, and there is lots of play equipment.”